function isok = usejava(feature)

%USEJAVA  True if the specified Java feature is supported in MATLAB.

%   USEJAVA(LEVEL) returns 1 if the feature is supported and 

%   0 otherwise.

%

%   The following levels of support exist:

%

%   LEVEL      MEANING

%   -----------------------------------------------------

%   'jvm'      The Java Virtual Machine is running.

%   'awt'      AWT components are available.

%   'swing'    Swing components are available.

%   'desktop'  The MATLAB interactive desktop is running.

%

%   "AWT components" refers to Java's GUI components in the Abstract 

%   Window Toolkit.  "Swing components" refers to Java's lightweight 

%   GUI components in the Java Foundation Classes.

%

%   EXAMPLES:

%

%   If you want to write a MATLAB program that displays a Java Frame and want

%   to be robust to the case when there is no display set or no JVM

%   available, you can do the following:

%   

%   if usejava('awt')

%      myFrame = java.awt.Frame;

%   else

%      disp('Unable to open a Java Frame.');

%   end

%

%   If you want to write a MATLAB program that uses Java code and want it to

%   fail gracefully when run in a MATLAB session that does not have access

%   to a JVM, you can add the following check:

%

%   if ~usejava('jvm')

%      error([mfilename ' requires Java to run.']);

%   end

%

%   See also JAVACHK

%   Copyright 1984-2011 The MathWorks, Inc.

narginchk(1,1); 

isok = system_dependent('useJava',feature);